Gliding motility is a trait common to many bacteria, yet the mechanism(s) of gliding motility is(are) unknown. The majority of molecular studies on bacterial gliding motility have focussed on the myxobacterium Myxococcus xanthus. To broaden our understanding of gliding motility, molecular analyses of the motility systems of two distantly related gliding bacteria, Lysobacter enzymogenes and Cytophaga johnsonae, will be performed. These studies will involve development of genetic systems for these bacteria and isolation of motility and taxis mutants. Motility and axis genes will be cloned and analyzed. The motility behavior of wild type and mutant cells will be examined by time-lapse videomicroscopy, with particular emphasis on possible chemotactic responses. Many of the gliding bacteria play important roles in biodegradation, others are pathogenic, and others produce useful antibiotics. Therefore studies of their basic biology, including mechanisms of movement, could have practical value. In a broader sense, information on how these bacteria sense and respond to their environment could help us to understand sensory responses of higher organisms.